This invention relates to an internally insulated bellows assembly for conducting pressurized fluid between two components of a high temperature fluid pressure system, such as a gas turbine engine or the like.
It has been found that by internally insulating the case of a gas turbine engine, the cost of such engine can be significantly reduced because the case can be constructed from inexpensive carbon steel, rather than high temperature nickel based alloyed steel, such as necessary for the internal components of the engine.
A recuperator, on the other hand, functions best when it is externally insulated. Consequently, a problem exists in connecting the internally insulated case of the gas turbine engine to the externally insulated recuperator case due to the vast temperature differential therebetween which can cause undue thermal loading due to the thermal distortion between the cases.